The present invention relates to an internet forwarding method, and the related system therefor.
Such a internet forwarding method is already known in the art, e.g. from section 5, p. 16 of Internet draft “IP Network Address Translation (NAT) Terminology and Considerations” from the authors P. Srisuresh and M. Holdrege. This IETF internet-draft is published in Apr. 1999 at the IETF internet-site under the title “draft-ietf-nat-terminology-02.txt”. Therein, an internet forwarding system is described wherein a host in a private network needs internet connectivity because a host on the internet needs to contact the private host or the private host needs to contact an internet host. The context of the description is related to the internet access of a privately addressed network. In such a privately addressed network all hosts are, at boot time, assigned a private IP address to enable TCP communications inside the network. However, in order to offer Internet connectivity to a private host, a global IP address from a pool of IP-addresses, is assigned to this private host, when this internet connectivity is required.
Then the internal routing, within the privately addressed network, has to be managed in order to allow the establishment of a path through the privately addressed network to the private host with a globally assigned and legally registered IP-address. This in order to enable the communication between the privately addressed host and a host connected to the internet. To enable the communication a tunnel is established, connecting the edge router of the private network with the addressed private host. The establishment of a tunnel between the edge router of the private network and the addressed private host has the following disadvantages: the edge router is heavy loaded and needs to keep state information, which creates a single point of failure, subsequently resulting in a limited robustness of the tunnelling. No load balancing of the outgoing traffic is possible in case of use of tunnelling and additional header-overhead occurs because of encapsulation.